REFERENCE-BASED TOPOLOGYESTIMATED HARDPOINTS
This is an independent educational reconstruction of the2020–2024 rear-wheel-drive, left-hand-drive electric-crossover front-end architecture. It is not a manufacturer-produced, licensed or metrologically verified digital twin. It does not represent every market, VIN, casting revision or model refresh.
R2: corrections driven by the source images
Do not use R1 as a mechanical reference.Its lower fork ownership, generic joint studs, smooth nut bore, external ball-return loop and interfering bearing envelopes were wrong. R2 replaces them with a damper-owned fork and arm bushing, an upper pinch-stud joint, correctly oriented lower and tie-rod studs, matching recessed races, a contained return passage and separately supported bearing rings. The invented overhead scaffold has been removed. The stabilizer is now placed at the front of the subframe. The reconstructed steering casing has bored pinion access, an enclosed belt bay and bearing-retention shoulders.
Surface proportions and hardpoints are still reconstructed. Service images establish the arrangement and connections; they do not supply a metrology-grade solid model. Very small numerical link-closure errors do not establish OEM dimensional accuracy.
What the sources directly establish
The manufacturer's legacy service data describes an independent front suspension with an upper wishbone, separate lower control arms, a coaxial coil spring / telescopic damper and a stabilizer bar. Knuckle procedures separately identify the upper arm, lower lateral arm, lower compliance arm and tie-rod joints. Service illustrations guide the tall knuckle, split lower links and damper-to-lateral-arm arrangement. Steering is mechanically connected rack-and-pinion with electric assistance.
The ball-screw distinction matters
Thedriver turns the pinion, not the ball nut. This cutaway uses the parallel-axis belt-drive EPS principle described by a major steering supplier: an electric motor drives a toothed belt, which turns an axially retained ball nut; the threaded rack translates without rotating. Driver and assist torques act through different paths on the same rack. It is not a worm-and-sector / Pitman-arm recirculating-ball steering box and it is not steer-by-wire.
The public manufacturer sources cited here do not expose the exact internal ball-return design, thread lead or reduction ratio.A steering supplier’s public description is the reference for the defensible educational assist architecture, not proof of the supplier or internals of any production rack. The 8 mm lead, 3:1 pulley ratio, 107 displayed balls, 3.5-turn loaded path, return channel and tooth profiles are explicitly reconstructed. The half-wrap return route is a reconstructed passage inside the nut wall, not a production channel of any supplier or carmaker. Screw and nut raceways share the same lead and phase. Ball centres circulate at a symmetric rolling-centre approximation; preload, spin and elastic contact are not simulated. The raceways have 35 μm of display surface relief to prevent tessellation clipping; this is not a production clearance or preload value.
How the suspension is constrained
Each knuckle has six pose variables. Two fixed distances to the upper inner pivots, one to each lower-link inner pivot, one to the moving rack inner joint, and the requested wheel-centre height provide six constraints. A damped Newton solver closes all six simultaneously. The upper arm rotates about its inner pivot axis. Lower links and tie rods retain their lengths; their idealized bushings permit angular articulation without translation.
Spring seats follow the damper, the lower clevis follows the lateral arm, and the telescopic unit changes length. Both stabilizer drop links retain their length while the centre bar admits torsional twist. The column includes two phased Cardan joints; their small nonuniform velocity relation is included in the rack input. Geometry is prescribed quasi-statically: no mass, damping force, rubber compliance, road contact, alignment certification or tyre forces are computed.
Reference envelope and reconstruction settings
| Setting | Value / status |
|---|
| Wheel / tyre display | 19-inch barrel, nominal 255/45 envelope; illustrative rim design |
| Track / static camber | 1.636 m / 0°; reconstruction settings |
| Travel limits | ±55 mm wheel-centre jounce; demonstration limits, not production stops |
| Steering range | ±432° (2.4 turns total reference); rack stroke and effective ratios reconstructed |
| Pinion pitch radius / screw lead | 8 mm / 8 mm per revolution; educational estimates |
| Nominal brake envelope | 355 mm × 25 mm ventilated rotor reference; not all trim variants |
| Dimensions / surfaces | All hardpoints, castings, support sections, return geometry and clearances reconstructed; not manufacturing drawings |
Primary references
01 · Manufacturer service manual — suspension and steeringFront suspension architecture and joint / bushing descriptions.
02 · Manufacturer service manual — front knuckle, LH (RWD): remove and replaceSeparate knuckle connections and service illustrations.
03 · Manufacturer service manual — steering rack: remove and replaceRack placement, intermediate-shaft input, tie rods and subframe attachment; rack revisions vary.
04 · Owner’s manual — subsystemsRack-and-pinion electric steering and reference envelopes. This is a live manual, not proof of all legacy trim dimensions.
05 · Steering supplier — EPS with belt-drive servo unitSeparate pinion driver path and belt / ball-nut assistance. Generic EPS principle, not vehicle-specific internal CAD.
Service manual — upper arm and FUCA carrierTwo upper pivots, shared carrier and pinch-stud connection.
Service manual — lower lateral linkCrossbar mounting, intermediate damper-eye bushing and lower outer ball joint.
Service manual — spring / damper RWDThree top studs, lower fork and stabilizer attachment.
Service manual — compliance linkSeparate swept lower link and vertical inner bushing.
HD image — lateral link and its damper eyeOfficial standalone part image used to correct the fork / eye error.
HD image — complete spring / damperThe fork belongs to this assembly, not to the lateral link.
HD image — upper knuckle pinch connectionDownward upper ball stud, split clamp and transverse bolt.
HD image — tall knuckleHub bore, cast spine, lower mounting ears and steering arm.
HD image — upper armBroad U-shaped arm, two bushings and outboard socket.
HD image — FUCA / damper top carrierCompact cast carrier rather than an invented overhead frame.
Steering supplier — annotated belt-drive cutawaySeparate driver and assist paths; return channel integrated into the nut. Not manufacturer internal CAD.
Service manual — front stabilizer removal / installationFront-of-subframe mounting and rearward end arms; this corrects the former rear-mounted bar.
HD image — front stabilizer, underside viewDirect geometric reference for the bar mounting side and lever orientation.
Inspecting without misreading the model
Cutawayremoves the upper gear-shell sections, or the front longitudinal half in the enlarged ball study;X-raymakes enclosing structures translucent;Ghost wheelsreveals the suspension.Explodeddeliberately separates components for inspection and locks motion. Return to assembled view before interpreting mechanical constraints. Body supports are cropped structural context, not a complete body-in-white. The RWD reference intentionally has no front drive unit or driven halfshafts.
All visible geometry is procedural. No manufacturer or supplier photographs or CAD are redistributed. The source project includes solver tests, browser-test results and a coordinate table. The application itself runs without a network connection.
